1. Field of the Invention
The present invention relates to a pointing apparatus, and particularly to an optical mouse and a lens module thereof.
2. Description of Related Art
FIG. 1 is a schematic view of a lens module of a conventional optical mouse. Referring to FIG. 1, the lens module 100 of the conventional optical mouse includes a substrate 110 and three fixed rods 120, wherein the three fixed rods 120 extend from a light incident surface 112 of the substrate 110 along a predetermined direction. An accommodation space between the three fixed rods 120 is for accommodating a light source (not shown) of the optical mouse, and the light source is for providing a light beam to the light incident surface 112 of the substrate 110. In the conventional technique, the three fixed rods 120 are used to clip the light source to fix the light source.
In general, the lens module 100 is manufactured by injection molding, so the mold for molding the lens module 100 is needed to be designed before manufacturing the lens module 100. In the conventional technique, due to the lens module 100 having the three fixed rods 120 extended from the light incident surface 112 of the substrate 110, the structure of the mold is complicated and more sliding blocks are needed. Thus, the cost of the mold is expensive. Moreover, due to the structure of the module being complicated, the lens module 100 is not easy to be manufactured. Therefore, the time for manufacturing the lens module 100 is increased and the yield of the lens module 100 is reduced. In other words, the manufacturing cost of the convention lens module 100 is higher. Furthermore, the structure of each of the fixed rods 120 is weak due to its long and thin shape, and thus the fixed rods 120 are easily broken.